Astilbe plant named ‘Verswhite’

ABSTRACT

A new and distinct cultivar of  Astilbe  plant named ‘Verswhite’, characterized by its compact, upright and strong plant habit; strong and healthy foliage; freely and uniformly flowering habit; white-colored flowers; and good garden performance.

Botanical designation: Astilbe arendsii×Astilbe japonica.

Cultivar denomination: ‘Verswhite’.

BACKGROUND OF THE INVENTION

The present invention relates to a new and distinct cultivar of Astilbe,botanically known as Astilbe arendsii×Astilbe japonica and hereinafterreferred to by the name ‘Verswhite’.

The new Astilbe is a product of a planned breeding program conducted bythe Inventor in Haarlem, The Netherlands. The objective of the breedingprogram was to create new strong Astilbe cultivars with attractivefoliage and flower coloration.

The new Astilbe originated from a cross-pollination made by the Inventorin 2001 in Haarlem, The Netherlands, of an unnamed Astilbe arendsiiseedling selection, not patented, as the female, or seed, parent with anunnamed Astilbe japonica seedling selection, not patented, as the male,or pollen, parent. The new Astilbe was discovered and selected by theInventor as a single flowering plant within the progeny of the statedcross-pollination in a controlled greenhouse environment in Haarlem, TheNetherlands in 2003.

Asexual reproduction of the new Astilbe by divisions in a controlledenvironment in a greenhouse in Honselersdijk, The Netherlands since2003, has shown that the unique features of this new Astilbe are stableand reproduced true to type in successive generations.

SUMMARY OF THE INVENTION

The cultivar Verswhite has not been observed under all possibleenvironmental conditions. The phenotype may vary somewhat withvariations in environment and cultural practices such as temperature andlight intensity without, however, any variance in genotype.

The following traits have been repeatedly observed and are determined tobe the unique characteristics of ‘Verswhite’. These characteristics incombination distinguish ‘Verswhite’ as a new and distinct cultivar ofAstilbe:

-   -   1. Compact, upright and strong plant habit.    -   2. Strong and healthy foliage.    -   3. Freely and uniformly flowering habit.    -   4. White-colored flowers.    -   5. Good garden performance.

Plants of the new Astilbe differ primarily from plants of the parentselections in plant height and flowering habit as plants of the newAstilbe are more compact and more freely flowering than plants of theparent selections.

Plants of the new Astilbe can be compared to plants of the Astilbearendsii cultivar Deutschland, not patented. In side-by-side comparisonsconducted in Haarlem, The Netherlands, plants of the new Astilbe and thecultivar Deutschland differed in the following characteristics:

-   -   1. Plants of the new Astilbe were more compact than plants of        the cultivar Deutschland.    -   2. Plants of the new Astilbe were more freely flowering than        plants of the cultivar Deutschland.

BRIEF DESCRIPTION OF THE PHOTOGRAPHS

The accompanying colored photographs illustrate the overall appearanceof the new Astilbe, showing the colors as true as it is reasonablypossible to obtain in colored reproductions of this type. Colors in thephotographs may differ slightly from the color values cited in thedetailed botanical description which accurately describe the colors ofthe new Astilbe.

The photograph on the first sheet comprises a side perspective view of atypical flowering plant of ‘Verswhite’ grown in a container.

The photograph at the top of the second sheet is a close-up view of atypical inflorescence of ‘Verswhite’.

The photograph at the bottom of the second sheet is a close-up view ofthe upper surface of a typical leaf of ‘Verswhite’.

DETAILED BOTANICAL DESCRIPTION

The aforementioned photographs and following observations, measurementsand values describe plants grown in containers in Afferden, TheNetherlands, under commercial practice in during the early summer in anoutdoor nursery with day temperatures ranging from 12° C. to 30° C. andnight temperatures ranging from 5° C. to 15° C. Plants had been growingfor about one year when the photographs and description were taken. Inthe following description, color references are made to The RoyalHorticultural Society Colour Chart, 2001 Edition, except where generalterms of ordinary dictionary significance are used.

-   Botanical classification: Astilbe arendsii×Astilbe japonica cultivar    ‘Verswhite’.-   Parentage:    -   -   Female, or seed, parent.—Unnamed Astilbe arendsii seedling            selection, not patented.        -   Male, or pollen, parent.—Unnamed Astilbe japonica seedling            selection, not patented.-   Propagation:    -   -   Type.—By divisions.        -   Time to initiate roots.—About three weeks at 20° C.        -   Root description.—Thick, fleshy; brown in color.        -   Rooting habit.—Freely branching; moderately dense.-   Plant description:    -   -   Plant form/habit.—Herbaceous perennial. Compact, upright and            strong plant habit; roughly triangular. Flowering stems and            leaves basal; dense and bushy growth habit; moderate to low            vigor. Freely and uniformly flowering with numerous flowers            on branched panicles.        -   Growth rate.—Moderate to slow; from divisions, about 28            weeks are required to produce fully-grown flowering plants.        -   Plant height (soil level to top of foliar plane).—About 12.1            cm.        -   Plant height (soil level to top of inflorescences).—About            32.7 cm.        -   Plant width (spread).—About 39.5 cm.        -   Stem description.—Length: About 6.7 cm. Diameter: About            3.5 mm. Internode length: About 1.5 cm. Strength: Strong.            Texture: Sparsely pubescent. Color: 144A.-   Foliage description:    -   -   Arrangement.—Alternate; biternately compound.        -   Leaf length (excluding petiole).—About 19.2 cm.        -   Leaf width.—About 16.8 cm.        -   Lateral leaflet length.—About 5.2 cm.        -   Lateral leaflet width.—About 2.5 cm.        -   Terminal leaflet length.—About 7.5 cm.        -   Terminal leaflet width.—About 3.4 cm.        -   Lateral and terminal leaflet shape.—Elliptic to narrowly            ovate.        -   Lateral and terminal leaflet apex.—Acute.        -   Lateral and terminal leaflet base.—Rounded to attenuate.        -   Lateral and terminal leaflet margin.—Biserrate.        -   Lateral and terminal leaflet texture, upper and lower            surfaces.—Sparsely pubescent; slightly rough.        -   Lateral and terminal leaflet venation pattern.—Pinnate.        -   Lateral and terminal leaflet color.—Developing leaves, upper            surface: Between 143B and 144A. Developing leaves, lower            surface: 143C. Fully expanded leaves, upper surface: Darker            than between 139A to 147A; venation, 147B. Fully expanded            leaves, lower surface: 147B; venation, 147B to 147C.        -   Leaf petiole length.—About 6.5 cm.        -   Leaf petiole diameter.—About 1.5 mm.        -   Leaflet petiole length.—About 7 mm.        -   Leaflet petiole width.—About 1.5 mm.        -   Leaf and leaflet petiole texture, upper and lower            surfaces.—Smooth, glabrous.        -   Leaf petiole color, upper and lower surfaces.—146A to 146B;            at the nodes, 187B.        -   Leaflet petiole color, upper and lower surfaces.—187B.-   Flower description:    -   -   Flower type/habit.—Numerous single rotate flowers arrange on            branched panicles; flowers fact upright, outward or downward            depending on position on the panicle. Panicles conical in            shape. Freely and uniformly flowering habit with about 2,000            flowers developing per inflorescence.        -   Fragrance.—Faintly fragrant; sweet.        -   Natural flowering season.—Continuously flowering during the            early summer for about six weeks in The Netherlands.        -   Postproduction longevity.—Flowers last about ten days on the            plant. Flowers persistent.        -   Flower buds.—Height: About 2.5 mm. Diameter: About 1.5 mm.            Shape: Ovate. Color: Close to 155D; towards the base, 144B.        -   Inflorescence Height.—About 23 cm.        -   Inflorescence diameter.—About 17.6 cm.        -   Flower diameter.—About 9 mm.        -   Flower depth.—About 3 mm.        -   Petals.—Quantity per flower: Typically five in a single            whorl. Length: About 4 mm. Lobe width: About 1 mm. Shape:            Narrowly oblanceolate. Apex: Acute. Margin: Entire. Texture,            upper and lower surfaces: Smooth, glabrous. Color:            Developing petals, upper and lower surfaces: Close to 155D.            Fully expanded petals, upper and lower surfaces: Close to            155D.        -   Sepals.—Quantity per flower: Typically five in a single            whorl, fused towards the base; campanulate calyx. Length:            About 2 mm. Width: About 1 mm. Shape: Broadly ovate. Apex:            Acute. Margin: Entire. Texture, upper and lower surfaces:            Smooth, glabrous. Color: Developing sepals, upper and lower            surfaces: 145A. Fully expanded sepals, upper and lower            surfaces: Close to 155D.        -   Peduncles.—Length: About 22.5 cm. Diameter: About 2.5 mm.            Angle: Erect. Strength: Strong. Texture: Smooth, glabrous.            Color: 146B to 146C flushed with 176B to 176C.        -   Pedicels.—Length: About 1.5 mm. Diameter: About 0.5 mm.            Angle: About 45° from vertical. Strength: Moderately strong.            Texture: Smooth, glabrous. Color: 145A to 145B.        -   Reproductive organs.—Stamens: Quantity per flower: Typically            ten; anthers basifixed. Filament length: About 2.5 mm.            Filament color: Close to 155D. Anther shape: Ovate. Anther            length: About 0.4 mm. Anther color: Close to 155D. Pollen            amount: Scarce. Pollen color: 155D. Pistils: Quantity per            flower: Two. Pistil length: About 2 mm. Stigma shape:            Club-shaped. Stigma color: 155A. Style length: About 1.6 mm.            Style color: Close to 155D. Ovary color: Close to 155D.        -   Seed/fruit.—Seed and fruit development have not been            observed.-   Disease/pest resistance: Plants of the new Astilbe have not been    noted to be resistant to pathogens and pests common to Astilbe.-   Garden performance: Plants of the new Astilbe have been observed to    have good garden performance and tolerate rain, wind and high    temperatures of about 35° C. Plants of the new Astilbe have been    observed to be hardy to USDA Zone 5.

1. A new and distinct Astilbe plant named ‘Verswhite’ as illustrated anddescribed.